The head, believed to date from between 1370 and 1380, is decorated with intricate braids in fashion at the time and is “well preserved despite light damage to the nose and lips,” according to the Piasa auction house.

The auction house said the exact journey of the effigy from its removal during the revolution to its reappearance in the hands of a Belgian antiques dealer more than fifty years ago “will doubtless remain a mystery.”

“It was detached, preserved, then haggled over; sold to a trafficker in royal goods; bought by an admirer of the Ancien Regime; taken across the frontier before falling into the hands of the antiques trade; and finally acquired by a Belgian engineer enamoured of beautiful objects.”